Hey Shiv,

I was at the last GA dyno day and you tuned my stage 1+ MR with 300.6awhp on andrew's dyno.

But I went back to a local dyno jet last weekend (the same dyno I did my base line run, I wanted to see the difference in my mods from stock dyno). I have been told that a dyno jet should read about 17% higher then Andrew's DD.

Well to say the least my #'s were very dissapointing and my air/fuel seems to be a little lean. I have changed nothing since the tune and i was using sunnoco 93 octane. Any Ideas about what could be wrong? do these Air/fuels seem lean to you?



Thanks, Chris

 

Hi Chris,
The AFRs are no lean so there is no reason to worry. I see knock retard at 6200rpm, causing a loss of 10-15whp up top. Without this retard, the car would make, by my estimates, 320-325whp. A few questions: Who's dyno is this and what kind of fans do they have?

shiv

 

dont get caught up in the numbers game between dynos. FWIW- Some dynojets read only 12% higher, that would make your 300whp ---> 335 whp. Like shiv said, it was on its way up, then that drop.

I wouldnt worry too much about the a/f ratios, as long as there are no big dips in the graphs (indicating knock).

 

Hey shiv,

The dyno was a local shop here in northern Va, its called Ultimate performance, and they use one big shop fan similar to the one used on andrew's DD, just not activated by the dyno this one has a little manual switch (how old school, haha )

this graph is SAE corrected and at 5% smoothing if that makes any difference to you

Chris

 

Ultimate performance dyno reads lower (from what I've seen) than regular dynojets.

 

I'm really not too concerned about the horsepower #'s, I just thought that the AFR's were a little lean. I thought maybe they were so lean that my ecu was sensing knock and pulling timing. I never wanted my car to be a horsepower monstar, I just want it to run safe with a decent amount of power.

Shiv, I am going to a 3 day track event at the end of this month, there will be about 6 hours of track time, So you think that this AFR is safe enough for me not to worry? I was planing on running a mixture of 93octane and some race gas just for piece of mind but if you insist that my AFR is safe then I wont waste the money on the race gas

thanks, Chris

 

The AFR on your car look really similar to mine. I've been running my car this way for the past 8 months without any problems. Do you know what you are boosting to on the top end? If it makes you feel any better you could dial some boost out on the top end from 6000rpm and up, probably 5 clicks. That should take care of the dip in power. As for the track event I would recommend running some race gas due to the sustained WOT conditions and hi temps. It’s just for a margin of safety, even if you were not tuned.

 

Chris-

If I was going to a track day with any tuned turbo car, I'd splash about 3 gallons of race gas in with the 93. Not only will it perform better, but the safety factor with the race gas is increased dramatically.

 

Chris - I am assuming you're going to Summit Point? Just fill up with 100 at the track; cost ya about $60. Funny as gas $$ go up - 100 octane stays at $4.99/gallon

Be sure to have SS brake lines and good fluid too

 

i recently experience the same thing too not long ago for those of you who remember it. They dynoed my car in 4th though when it supposedly shoulda been 3rd?

 

I think 4th gear is closest to 1:1 on the MR

 

and ours is 3rd?

 

yes, for the 5-speed

 

Yup, I will be going to summit point! I just ordered my works SS brake lines and some synthetic brake fluid... only problem is that I will be using stock pads ... I dont have the money to upgrade them this month, besides they only have 4K miles on them. I just hope they dont glaze over by the second day.

I hope stock pads will hold up for me.... I mean this is why I bought this car, It was supposed to be drive it to the track on sunday, and then drive it to work on monday type of car right!!! at least thats what I thought

....

okay I will use race gas on the track but what about some spirited street driving, are my AFR safe or NO? All I wanted was a safe street map. I am in no way a tunner (thats why I pay pro's for this type of thing) When I ran my dyno they quickly pulled me off saying I was too lean and should not push my car. This is a little upsetting considering I just paid all this money for a custom tune.

All I would like to hear is YES car is 100% safe to drive hard or NO you are running a little lean get this fixed before any damage can be done to your VERY expensive engine...

 

YES, the car is fine. There are very many EVO's running around with this kind of tune with no problems. Did you compare the new AFR's to the AFR's you received at Dyno4mance?

Also, what did the other 4 dyno runs look like?